I've saved one of the best for last: Duke's. This elegant, small hotel bar is a temple to the martini. I could see why it was frequented by James Bond author Ian Fleming and other martini lovers over the years. I cannot recall a more perfect martini. Head barman Alessandro Palazzi is among the most delightful, consummate bartenders I've had the pleasure to be served by. As he wheeled out a trolley laden with olives, lemons, ice, and gorgeous barware, he immediately impressed with his expert gin knowledge.

Asking where we were from, he launched into a rapturous account of his love for San Francisco gins 209 and Junipero, saying he's long been extolling the glories of Junipero. Well-versed and intimately acquainted with the best gins the world over, he dropped distiller names like "Arne" and "Fritz."

I asked for London's Sipsmith gin. Alessandro proceeded to bring out a sample of another locally-produced, small distiller Sacred so we could compare side-by-side. He mixed our martinis to icy perfection, gin's bite tempered with the refreshing cool of dry vermouth and a hint of lemon. This tiny, quiet haven remains among my favorite memories of London, an impeccable martini immaculately served lingering in my mind.